Oil refineries in central Russia have been forced to either suspend operations entirely or sharply reduce fuel output after a wave of drone attacks over the past two weeks, Reuters reported Tuesday, citing official data and industry sources.

Russia has already banned gasoline exports until July 31 as Ukraine ramps up its attacks against energy sites across the country in a bid to deprive the Kremlin of windfalls from surging oil prices.

The number of refineries targeted by Ukrainian drones has doubled since the start of the year, Reuters said.

Several major plants in central Russia, a key refining hub supplying domestic consumers and contributing a substantial share of fuel exports, have largely ground to a halt this month.

Among the large refineries targeted were plants in Kirishi, Moscow, Nizhny Novgorod, Ryazan and Yaroslavl.